Techniques and apparatuses for modulation order control for an uplink channel

ABSTRACT

Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a user equipment (UE) may receive, while the UE is using a first modulation order for a physical uplink control channel, a signaling message that identifies a second modulation order, for the physical uplink control channel. The UE may provide the physical uplink control channel using the second modulation order. In some aspects, a base station may provide, while a UE is using a first modulation order for a physical uplink control channel, a signaling message that identifies a second modulation order, for the physical uplink control channel. The base station may receive the physical uplink control channel using the second modulation order. Numerous other aspects are provided.

CROSS-REFERENCE TO RELATED APPLICATIONS UNDER 35 U.S.C. § 119

This application claims priority to Provisional Patent Application No. 62/576,041, filed on Oct. 23, 2017, entitled “TECHNIQUES AND APPARATUSES FOR MODULATION ORDER CONTROL FOR AN UPLINK CHANNEL,” which is hereby expressly incorporated by reference herein.

FIELD OF THE DISCLOSURE

Aspects of the present disclosure generally relate to wireless communication, and more particularly to techniques and apparatuses for modulation order control for a physical uplink control channel.

BACKGROUND

Wireless communication systems are widely deployed to provide various telecommunication services such as telephony, video, data, messaging, and broadcasts. Typical wireless communication systems may employ multiple-access technologies capable of supporting communication with multiple users by sharing available system resources (e.g., bandwidth, transmit power, and/or the like). Examples of such multiple-access technologies include code division multiple access (CDMA) systems, time division multiple access (TDMA) systems, frequency-division multiple access (FDMA) systems, orthogonal frequency-division multiple access (OFDMA) systems, single-carrier frequency-division multiple access (SC-FDMA) systems, time division synchronous code division multiple access (TD-SCDMA) systems, and Long Term Evolution (LTE). LTE/LTE-Advanced is a set of enhancements to the Universal Mobile Telecommunications System (UMTS) mobile standard promulgated by the Third Generation Partnership Project (3GPP).

A wireless communication network may include a number of base stations (BSs) that can support communication for a number of user equipment (UEs). A user equipment (UE) may communicate with a base station (BS) via the downlink and uplink. The downlink (or forward link) refers to the communication link from the BS to the UE, and the uplink (or reverse link) refers to the communication link from the UE to the BS. As will be described in more detail herein, a BS may be referred to as a Node B, a gNB, an access point (AP), a radio head, a transmit receive point (TRP), a new radio (NR) BS, a 5G Node B, and/or the like.

The above multiple access technologies have been adopted in various telecommunication standards to provide a common protocol that enables different user equipment to communicate on a municipal, national, regional, and even global level. New radio (NR), which may also be referred to as 5G, is a set of enhancements to the LTE mobile standard promulgated by the Third Generation Partnership Project (3GPP). NR is designed to better support mobile broadband Internet access by improving spectral efficiency, lowering costs, improving services, making use of new spectrum, and better integrating with other open standards using orthogonal frequency division multiplexing (OFDM) with a cyclic prefix (CP) (CP-OFDM) on the downlink (DL), using CP-OFDM and/or SC-FDM (e.g., also known as discrete Fourier transform spread OFDM (DFT-s-OFDM)) on the uplink (UL), as well as supporting beamforming, multiple-input multiple-output (MIMO) antenna technology, and carrier aggregation. However, as the demand for mobile broadband access continues to increase, there exists a need for further improvements in LTE and NR technologies. Preferably, these improvements should be applicable to other multiple access technologies and the telecommunication standards that employ these technologies.

SUMMARY

In some aspects, a method of wireless communication may include receiving, while a user equipment (UE) is using a first modulation order for a physical uplink control channel, a signaling message that identifies a second modulation order, for the physical uplink control channel, selected based at least in part on a link budget of the UE, wherein the second modulation order is different from the first modulation order. The method may include providing the physical uplink control channel using the second modulation order.

In some aspects, a UE for wireless communication may include memory and one or more processors operatively coupled to the memory. The memory and the one or more processors may be configured to receive, while the UE is using a first modulation order for a physical uplink control channel, a signaling message that identifies a second modulation order, for the physical uplink control channel, selected based at least in part on a link budget of the UE, wherein the second modulation order is different from the first modulation order. The memory and the one or more processors may be configured to provide the physical uplink control channel using the second modulation order.

In some aspects, a non-transitory computer-readable medium may store one or more instructions for wireless communication. The one or more instructions, when executed by one or more processors of a UE, may cause the one or more processors to receive, while the UE is using a first modulation order for a physical uplink control channel, a signaling message that identifies a second modulation order, for the physical uplink control channel, selected based at least in part on a link budget of the UE, wherein the second modulation order is different from the first modulation order. The one or more instructions, when executed by the one or more processors, may cause the one or more processors to provide the physical uplink control channel using the second modulation order.

In some aspects, an apparatus for wireless communication may include means for receiving, while the apparatus is using a first modulation order for a physical uplink control channel, a signaling message that identifies a second modulation order, for the physical uplink control channel, selected based at least in part on a link budget of the UE, wherein the second modulation order is different from the first modulation order. The apparatus may include means for providing the physical uplink control channel using the second modulation order.

In some aspects, a method of wireless communication may include providing, while a UE is using a first modulation order for a physical uplink control channel, a signaling message that identifies a second modulation order, for the physical uplink control channel, selected based at least in part on a link budget of the UE, wherein the second modulation order is different from the first modulation order. The method may include receiving the physical uplink control channel using the second modulation order.

In some aspects, a base station for wireless communication may include memory and one or more processors operatively coupled to the memory. The memory and the one or more processors may be configured to provide, while a UE is using a first modulation order for a physical uplink control channel, a signaling message that identifies a second modulation order, for the physical uplink control channel, selected based at least in part on a link budget of the UE, wherein the second modulation order is different from the first modulation order. The memory and the one or more processors may be configured to receive the physical uplink control channel using the second modulation order.

In some aspects, a non-transitory computer-readable medium may store one or more instructions for wireless communication. The one or more instructions, when executed by one or more processors of a base station, may cause the one or more processors to provide, while a UE is using a first modulation order for a physical uplink control channel, a signaling message that identifies a second modulation order, for the physical uplink control channel, selected based at least in part on a link budget of the UE, wherein the second modulation order is different from the first modulation order. The one or more instructions, when executed by the one or more processors, may cause the one or more processors to receive the physical uplink control channel using the second modulation order.

In some aspects, an apparatus for wireless communication may include means for providing, while a UE is using a first modulation order for a physical uplink control channel, a signaling message that identifies a second modulation order, for the physical uplink control channel, selected based at least in part on a link budget of the UE, wherein the second modulation order is different from the first modulation order. The apparatus may include means for receiving the physical uplink control channel using the second modulation order.

Aspects generally include a method, apparatus, device, computer program product, non-transitory computer-readable medium, user equipment, wireless communication device, base station, access point, and processing system as substantially described herein with reference to and as illustrated by the accompanying drawings and specification.

The foregoing has outlined rather broadly the features and technical advantages of examples according to the disclosure in order that the detailed description that follows may be better understood. Additional features and advantages will be described hereinafter. The conception and specific examples disclosed may be readily utilized as a basis for modifying or designing other structures for carrying out the same purposes of the present disclosure. Such equivalent constructions do not depart from the scope of the appended claims. Characteristics of the concepts disclosed herein, both their organization and method of operation, together with associated advantages will be better understood from the following description when considered in connection with the accompanying figures. Each of the figures is provided for the purpose of illustration and description, and not as a definition of the limits of the claims.

BRIEF DESCRIPTION OF THE DRAWINGS

So that the manner in which the above-recited features of the present disclosure can be understood in detail, a more particular description, briefly summarized above, may be had by reference to aspects, some of which are illustrated in the appended drawings. It is to be noted, however, that the appended drawings illustrate only certain typical aspects of this disclosure and are therefore not to be considered limiting of its scope, for the description may admit to other equally effective aspects. The same reference numbers in different drawings may identify the same or similar elements.

FIG. 1 is a block diagram conceptually illustrating an example of a wireless communication network, in accordance with various aspects of the present disclosure.

FIG. 2 is a block diagram conceptually illustrating an example of a base station in communication with a user equipment (UE) in a wireless communication network, in accordance with various aspects of the present disclosure.

FIG. 3 is a block diagram conceptually illustrating an example of a frame structure in a wireless communication network, in accordance with various aspects of the present disclosure.

FIG. 4 is a block diagram conceptually illustrating two example subframe formats with the normal cyclic prefix, in accordance with various aspects of the present disclosure.

FIG. 5 illustrates an example logical architecture of a distributed radio access network (RAN), in accordance with various aspects of the present disclosure.

FIG. 6 illustrates an example physical architecture of a distributed RAN, in accordance with various aspects of the present disclosure.

FIGS. 7A and 7B are diagrams illustrating an example of modulation order control for a physical uplink control channel, in accordance with various aspects of the present disclosure.

FIG. 8 is a diagram illustrating an example process performed, for example, by a user equipment, in accordance with various aspects of the present disclosure.

FIG. 9 is a diagram illustrating an example process performed, for example, by a base station, in accordance with various aspects of the present disclosure.

DETAILED DESCRIPTION

Various aspects of the disclosure are described more fully hereinafter with reference to the accompanying drawings. This disclosure may, however, be embodied in many different forms and should not be construed as limited to any specific structure or function presented throughout this disclosure. Rather, these aspects are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art. Based at least in part on the teachings herein one skilled in the art should appreciate that the scope of the disclosure is intended to cover any aspect of the disclosure disclosed herein, whether implemented independently of or combined with any other aspect of the disclosure. For example, an apparatus may be implemented or a method may be practiced using any number of the aspects set forth herein. In addition, the scope of the disclosure is intended to cover such an apparatus or method which is practiced using other structure, functionality, or structure and functionality in addition to or other than the various aspects of the disclosure set forth herein. It should be understood that any aspect of the disclosure disclosed herein may be embodied by one or more elements of a claim.

Several aspects of telecommunication systems will now be presented with reference to various apparatuses and techniques. These apparatuses and techniques will be described in the following detailed description and illustrated in the accompanying drawings by various blocks, modules, components, circuits, steps, processes, algorithms, and/or the like (collectively referred to as “elements”). These elements may be implemented using hardware, software, or combinations thereof. Whether such elements are implemented as hardware or software depends upon the particular application and design constraints imposed on the overall system.

It is noted that while aspects may be described herein using terminology commonly associated with 3G and/or 4G wireless technologies, aspects of the present disclosure can be applied in other generation-based communication systems, such as 5G and later, including NR technologies.

FIG. 1 is a diagram illustrating a network 100 in which aspects of the present disclosure may be practiced. The network 100 may be an LTE network or some other wireless network, such as a 5G or NR network. Wireless network 100 may include a number of BSs 110 (shown as BS 110 a, BS 110 b, BS 110 c, and BS 110 d) and other network entities. A BS is an entity that communicates with user equipment (UEs) and may also be referred to as a base station, a NR BS, a Node B, a gNB, a 5G node B (NB), an access point, a transmit receive point (TRP), and/or the like. Each BS may provide communication coverage for a particular geographic area. In 3GPP, the term “cell” can refer to a coverage area of a BS and/or a BS subsystem serving this coverage area, depending on the context in which the term is used.

A BS may provide communication coverage for a macro cell, a pico cell, a femto cell, and/or another type of cell. A macro cell may cover a relatively large geographic area (e.g., several kilometers in radius) and may allow unrestricted access by UEs with service subscription. A pico cell may cover a relatively small geographic area and may allow unrestricted access by UEs with service subscription. A femto cell may cover a relatively small geographic area (e.g., a home) and may allow restricted access by UEs having association with the femto cell (e.g., UEs in a closed subscriber group (CSG)). A BS for a macro cell may be referred to as a macro BS. A BS for a pico cell may be referred to as a pico BS. A BS for a femto cell may be referred to as a femto BS or a home BS. In the example shown in FIG. 1, a BS 110 a may be a macro BS for a macro cell 102 a, a BS 110 b may be a pico BS for a pico cell 102 b, and a BS 110 c may be a femto BS for a femto cell 102 c. A BS may support one or multiple (e.g., three) cells. The terms “eNB”, “base station”, “NR BS”, “gNB”, “TRP”, “AP”, “node B”, “5G NB”, and “cell” may be used interchangeably herein.

In some aspects, a cell may not necessarily be stationary, and the geographic area of the cell may move according to the location of a mobile BS. In some aspects, the BSs may be interconnected to one another and/or to one or more other BSs or network nodes (not shown) in the access network 100 through various types of backhaul interfaces such as a direct physical connection, a virtual network, and/or the like using any suitable transport network.

Wireless network 100 may also include relay stations. A relay station is an entity that can receive a transmission of data from an upstream station (e.g., a BS or a UE) and send a transmission of the data to a downstream station (e.g., a UE or a BS). A relay station may also be a UE that can relay transmissions for other UEs. In the example shown in FIG. 1, a relay station 110 d may communicate with macro BS 110 a and a UE 120 d in order to facilitate communication between BS 110 a and UE 120 d. A relay station may also be referred to as a relay BS, a relay base station, a relay, and/or the like.

Wireless network 100 may be a heterogeneous network that includes BSs of different types, e.g., macro BSs, pico BSs, femto BSs, relay BSs, and/or the like. These different types of BSs may have different transmit power levels, different coverage areas, and different impact on interference in wireless network 100. For example, macro BSs may have a high transmit power level (e.g., 5 to 40 Watts) whereas pico BSs, femto BSs, and relay BSs may have lower transmit power levels (e.g., 0.1 to 2 Watts).

A network controller 130 may couple to a set of BSs and may provide coordination and control for these BSs. Network controller 130 may communicate with the BSs via a backhaul. The BSs may also communicate with one another, e.g., directly or indirectly via a wireless or wireline backhaul.

UEs 120 (e.g., 120 a, 120 b, 120 c) may be dispersed throughout wireless network 100, and each UE may be stationary or mobile. A UE may also be referred to as an access terminal, a terminal, a mobile station, a subscriber unit, a station, and/or the like. A UE may be a cellular phone (e.g., a smart phone), a personal digital assistant (PDA), a wireless modem, a wireless communication device, a handheld device, a laptop computer, a cordless phone, a wireless local loop (WLL) station, a tablet, a camera, a gaming device, a netbook, a smartbook, an ultrabook, medical device or equipment, biometric sensors/devices, wearable devices (smart watches, smart clothing, smart glasses, smart wrist bands, smart jewelry (e.g., smart ring, smart bracelet)), an entertainment device (e.g., a music or video device, or a satellite radio), a vehicular component or sensor, smart meters/sensors, industrial manufacturing equipment, a global positioning system device, or any other suitable device that is configured to communicate via a wireless or wired medium.

Some UEs may be considered machine-type communication (MTC) or evolved or enhanced machine-type communication (eMTC) UEs. MTC and eMTC UEs include, for example, robots, drones, remote devices, such as sensors, meters, monitors, location tags, and/or the like, that may communicate with a base station, another device (e.g., remote device), or some other entity. A wireless node may provide, for example, connectivity for or to a network (e.g., a wide area network such as Internet or a cellular network) via a wired or wireless communication link. Some UEs may be considered Internet-of-Things (IoT) devices, and/or may be implemented as may be implemented as NB-IoT (narrowband internet of things) devices. Some UEs may be considered a Customer Premises Equipment (CPE). UE 120 may be included inside a housing that houses components of UE 120, such as processor components, memory components, and/or the like.

In general, any number of wireless networks may be deployed in a given geographic area. Each wireless network may support a particular RAT and may operate on one or more frequencies. A RAT may also be referred to as a radio technology, an air interface, and/or the like. A frequency may also be referred to as a carrier, a frequency channel, and/or the like. Each frequency may support a single RAT in a given geographic area in order to avoid interference between wireless networks of different RATs. In some cases, NR or 5G RAT networks may be deployed.

In some aspects, two or more UEs 120 (e.g., shown as UE 120 a and UE 120 e) may communicate directly using one or more sidelink channels (e.g., without using a base station 110 as an intermediary to communicate with one another). For example, the UEs 120 may communicate using peer-to-peer (P2P) communications, device-to-device (D2D) communications, a vehicle-to-everything (V2X) protocol (e.g., which may include a vehicle-to-vehicle (V2V) protocol, a vehicle-to-infrastructure (V2I) protocol, and/or the like), a mesh network, and/or the like. In this case, the UE 120 may perform scheduling operations, resource selection operations, and/or other operations described elsewhere herein as being performed by the base station 110.

As indicated above, FIG. 1 is provided merely as an example. Other examples are possible and may differ from what was described with regard to FIG. 1.

FIG. 2 shows a block diagram of a design 200 of base station 110 and UE 120, which may be one of the base stations and one of the UEs in FIG. 1. Base station 110 may be equipped with T antennas 234 a through 234 t, and UE 120 may be equipped with R antennas 252 a through 252 r, where in general T≥1 and R≥1.

At base station 110, a transmit processor 220 may receive data from a data source 212 for one or more UEs, select one or more modulation and coding schemes (MCS) for each UE based at least in part on channel quality indicators (CQIs) received from the UE, process (e.g., encode and modulate) the data for each UE based at least in part on the MCS(s) selected for the UE, and provide data symbols for all UEs. Transmit processor 220 may also process system information (e.g., for semi-static resource partitioning information (SRPI) and/or the like) and control information (e.g., CQI requests, grants, upper layer signaling, and/or the like) and provide overhead symbols and control symbols. Transmit processor 220 may also generate reference symbols for reference signals (e.g., the cell-specific reference signal (CRS)) and synchronization signals (e.g., the primary synchronization signal (PSS) and secondary synchronization signal (SSS)). A transmit (TX) multiple-input multiple-output (MIMO) processor 230 may perform spatial processing (e.g., precoding) on the data symbols, the control symbols, the overhead symbols, and/or the reference symbols, if applicable, and may provide T output symbol streams to T modulators (MODs) 232 a through 232 t. Each modulator 232 may process a respective output symbol stream (e.g., for OFDM and/or the like) to obtain an output sample stream. Each modulator 232 may further process (e.g., convert to analog, amplify, filter, and upconvert) the output sample stream to obtain a downlink signal. T downlink signals from modulators 232 a through 232 t may be transmitted via T antennas 234 a through 234 t, respectively. According to various aspects described in more detail below, the synchronization signals can be generated with location encoding to convey additional information.

At UE 120, antennas 252 a through 252 r may receive the downlink signals from base station 110 and/or other base stations and may provide received signals to demodulators (DEMODs) 254 a through 254 r, respectively. Each demodulator 254 may condition (e.g., filter, amplify, downconvert, and digitize) a received signal to obtain input samples. Each demodulator 254 may further process the input samples (e.g., for OFDM and/or the like) to obtain received symbols. A MIMO detector 256 may obtain received symbols from all R demodulators 254 a through 254 r, perform MIMO detection on the received symbols if applicable, and provide detected symbols. A receive processor 258 may process (e.g., demodulate and decode) the detected symbols, provide decoded data for UE 120 to a data sink 260, and provide decoded control information and system information to a controller/processor 280. A channel processor may determine reference signal received power (RSRP), received signal strength indicator (RSSI), reference signal received quality (RSRQ), channel quality indicator (CQI), and/or the like.

On the uplink, at UE 120, a transmit processor 264 may receive and process data from a data source 262 and control information (e.g., for reports comprising RSRP, RSSI, RSRQ, CQI, and/or the like) from controller/processor 280. Transmit processor 264 may also generate reference symbols for one or more reference signals. The symbols from transmit processor 264 may be precoded by a TX MIMO processor 266 if applicable, further processed by modulators 254 a through 254 r (e.g., for DFT-s-OFDM, CP-OFDM, and/or the like), and transmitted to base station 110. At base station 110, the uplink signals from UE 120 and other UEs may be received by antennas 234, processed by demodulators 232, detected by a MIMO detector 236 if applicable, and further processed by a receive processor 238 to obtain decoded data and control information sent by UE 120. Receive processor 238 may provide the decoded data to a data sink 239 and the decoded control information to controller/processor 240. Base station 110 may include communication unit 244 and communicate to network controller 130 via communication unit 244. Network controller 130 may include communication unit 294, controller/processor 290, and memory 292. In some aspects, one or more components of UE 120 may be included in a housing.

Controller/processor 240 of base station 110, controller/processor 280 of UE 120, and/or any other component(s) of FIG. 2 may perform one or more techniques associated with modulation order control for a physical uplink control channel, as described in more detail elsewhere herein. For example, controller/processor 240 of base station 110, controller/processor 280 of UE 120, and/or any other component(s) of FIG. 2 may perform or direct operations of, for example, process 800 of FIG. 8, process 900 of FIG. 9, and/or other processes as described herein. Memories 242 and 282 may store data and program codes for base station 110 and UE 120, respectively. A scheduler 246 may schedule UEs for data transmission on the downlink and/or uplink.

In some aspects, UE 120 may include means for receiving, while UE 120 is using a first modulation order for a physical uplink control channel, a signaling message that identifies a second modulation order, for the physical uplink control channel, selected based at least in part on a link budget of UE 120, means for providing the physical uplink control channel using the second modulation order, and/or the like. In some aspects, such means may include one or more components of UE 120 described in connection with FIG. 2.

In some aspects, base station 110 may include means for providing, while UE 120 is using a first modulation order for a physical uplink control channel, a signaling message that identifies a second modulation order, for the physical uplink control channel, selected based at least in part on a link budget of UE 120, means for receiving the physical uplink control channel using the second modulation order, and/or the like. In some aspects, such means may include one or more components of base station 110 described in connection with FIG. 2.

As indicated above, FIG. 2 is provided merely as an example. Other examples are possible and may differ from what was described with regard to FIG. 2.

FIG. 3 shows an example frame structure 300 for frequency division duplexing (FDD) in a telecommunications system (e.g., LTE). The transmission timeline for each of the downlink and uplink may be partitioned into units of radio frames. Each radio frame may have a predetermined duration (e.g., 10 milliseconds (ms)) and may be partitioned into 10 subframes with indices of 0 through 9. Each subframe may include two slots. Each radio frame may thus include 20 slots with indices of 0 through 19. Each slot may include L symbol periods, e.g., seven symbol periods for a normal cyclic prefix (as shown in FIG. 3) or six symbol periods for an extended cyclic prefix. The 2 L symbol periods in each subframe may be assigned indices of 0 through 2 L−1.

While some techniques are described herein in connection with frames, subframes, slots, and/or the like, these techniques may equally apply to other types of wireless communication structures, which may be referred to using terms other than “frame,” “subframe,” “slot,” and/or the like in 5G NR. In some aspects, a wireless communication structure may refer to a periodic time-bounded communication unit defined by a wireless communication standard and/or protocol.

In certain telecommunications (e.g., LTE), a BS may transmit a primary synchronization signal (PSS) and a secondary synchronization signal (SSS) on the downlink in the center of the system bandwidth for each cell supported by the BS. The PSS and SSS may be transmitted in symbol periods 6 and 5, respectively, in subframes 0 and 5 of each radio frame with the normal cyclic prefix, as shown in FIG. 3. The PSS and SSS may be used by UEs for cell search and acquisition. The BS may transmit a cell-specific reference signal (CRS) across the system bandwidth for each cell supported by the BS. The CRS may be transmitted in certain symbol periods of each subframe and may be used by the UEs to perform channel estimation, channel quality measurement, and/or other functions. The BS may also transmit a physical broadcast channel (PBCH) in symbol periods 0 to 3 in slot 1 of certain radio frames. The PBCH may carry some system information. The BS may transmit other system information such as system information blocks (SIBs) on a physical downlink shared channel (PDSCH) in certain subframes. The BS may transmit control information/data on a physical downlink control channel (PDCCH) in the first B symbol periods of a subframe, where B may be configurable for each subframe. The BS may transmit traffic data and/or other data on the PDSCH in the remaining symbol periods of each subframe.

In other systems (e.g., such as NR or 5G systems), a Node B may transmit these or other signals in these locations or in different locations of the subframe.

As indicated above, FIG. 3 is provided merely as an example. Other examples are possible and may differ from what was described with regard to FIG. 3.

FIG. 4 shows two example subframe formats 410 and 420 with the normal cyclic prefix. The available time frequency resources may be partitioned into resource blocks. Each resource block may cover 12 subcarriers in one slot and may include a number of resource elements. Each resource element may cover one subcarrier in one symbol period and may be used to send one modulation symbol, which may be a real or complex value.

Subframe format 410 may be used for two antennas. A CRS may be transmitted from antennas 0 and 1 in symbol periods 0, 4, 7, and 11. A reference signal is a signal that is known a priori by a transmitter and a receiver and may also be referred to as a pilot signal. A CRS is a reference signal that is specific for a cell, e.g., generated based at least in part on a cell identity (ID). In FIG. 4, for a given resource element with label Ra, a modulation symbol may be transmitted on that resource element from antenna a, and no modulation symbols may be transmitted on that resource element from other antennas. Subframe format 420 may be used with four antennas. A CRS may be transmitted from antennas 0 and 1 in symbol periods 0, 4, 7, and 11 and from antennas 2 and 3 in symbol periods 1 and 8. For both subframe formats 410 and 420, a CRS may be transmitted on evenly spaced subcarriers, which may be determined based at least in part on cell ID. CRSs may be transmitted on the same or different subcarriers, depending on their cell IDs. For both subframe formats 410 and 420, resource elements not used for the CRS may be used to transmit data (e.g., traffic data, control data, and/or other data).

The PSS, SSS, CRS and PBCH in LTE are described in 3GPP Technical Specification (TS) 36.211, entitled “Evolved Universal Terrestrial Radio Access (E-UTRA); Physical Channels and Modulation,” which is publicly available.

An interlace structure may be used for each of the downlink and uplink for FDD in certain telecommunications systems (e.g., LTE). For example, Q interlaces with indices of 0 through Q−1 may be defined, where Q may be equal to 4, 6, 8, 10, or some other value. Each interlace may include subframes that are spaced apart by Q frames. In particular, interlace q may include subframes q, q+Q, q+2Q, and/or the like, where q∈{0, . . . , Q−1}.

The wireless network may support hybrid automatic retransmission request (HARQ) for data transmission on the downlink and uplink. For HARQ, a transmitter (e.g., a BS) may send one or more transmissions of a packet until the packet is decoded correctly by a receiver (e.g., a UE) or some other termination condition is encountered. For synchronous HARQ, all transmissions of the packet may be sent in subframes of a single interlace. For asynchronous HARQ, each transmission of the packet may be sent in any subframe.

A UE may be located within the coverage of multiple BSs. One of these BSs may be selected to serve the UE. The serving BS may be selected based at least in part on various criteria such as received signal strength, received signal quality, path loss, and/or the like. Received signal quality may be quantified by a signal-to-noise-and-interference ratio (SINR), or a reference signal received quality (RSRQ), or some other metric. The UE may operate in a dominant interference scenario in which the UE may observe high interference from one or more interfering BSs.

While aspects of the examples described herein may be associated with LTE technologies, aspects of the present disclosure may be applicable with other wireless communication systems, such as NR or 5G technologies.

New radio (NR) may refer to radios configured to operate according to a new air interface (e.g., other than Orthogonal Frequency Divisional Multiple Access (OFDMA)-based air interfaces) or fixed transport layer (e.g., other than Internet Protocol (IP)). In aspects, NR may utilize OFDM with a CP (herein referred to as cyclic prefix OFDM or CP-OFDM) and/or SC-FDM on the uplink, may utilize CP-OFDM on the downlink and include support for half-duplex operation using time division duplexing (TDD). In aspects, NR may, for example, utilize OFDM with a CP (herein referred to as CP-OFDM) and/or discrete Fourier transform spread orthogonal frequency-division multiplexing (DFT-s-OFDM) on the uplink, may utilize CP-OFDM on the downlink and include support for half-duplex operation using TDD. NR may include Enhanced Mobile Broadband (eMBB) service targeting wide bandwidth (e.g., 80 megahertz (MHz) and beyond), millimeter wave (mmW) targeting high carrier frequency (e.g., 60 gigahertz (GHz)), massive MTC (mMTC) targeting non-backward compatible MTC techniques, and/or mission critical targeting ultra reliable low latency communications (URLLC) service.

A single component carrier bandwidth of 100 MHZ may be supported. NR resource blocks may span 12 sub-carriers with a sub-carrier bandwidth of 75 kilohertz (kHz) over a 0.1 ms duration. Each radio frame may include 50 subframes with a length of 10 ms. Consequently, each subframe may have a length of 0.2 ms. Each subframe may indicate a link direction (e.g., DL or UL) for data transmission and the link direction for each subframe may be dynamically switched. Each subframe may include downlink/uplink (DL/UL) data as well as DL/UL control data.

Beamforming may be supported and beam direction may be dynamically configured. MIMO transmissions with precoding may also be supported. MIMO configurations in the DL may support up to 8 transmit antennas with multi-layer DL transmissions up to 8 streams and up to 2 streams per UE. Multi-layer transmissions with up to 2 streams per UE may be supported. Aggregation of multiple cells may be supported with up to 8 serving cells. Alternatively, NR may support a different air interface, other than an OFDM-based interface. NR networks may include entities such central units or distributed units.

The RAN may include a central unit (CU) and distributed units (DUs). A NR BS (e.g., gNB, 5G Node B, Node B, transmit receive point (TRP), access point (AP)) may correspond to one or multiple BSs. NR cells can be configured as access cells (ACells) or data only cells (DCells). For example, the RAN (e.g., a central unit or distributed unit) can configure the cells. DCells may be cells used for carrier aggregation or dual connectivity, but not used for initial access, cell selection/reselection, or handover. In some cases, DCells may not transmit synchronization signals. In some cases, DCells may transmit synchronization signals. NR BSs may transmit downlink signals to UEs indicating the cell type. Based at least in part on the cell type indication, the UE may communicate with the NR BS. For example, the UE may determine NR BSs to consider for cell selection, access, handover, and/or measurement based at least in part on the indicated cell type.

As indicated above, FIG. 4 is provided merely as an example. Other examples are possible and may differ from what was described with regard to FIG. 4.

FIG. 5 illustrates an example logical architecture of a distributed RAN 500, according to aspects of the present disclosure. A 5G access node 506 may include an access node controller (ANC) 502. The ANC may be a central unit (CU) of the distributed RAN 500. The backhaul interface to the next generation core network (NG-CN) 504 may terminate at the ANC. The backhaul interface to neighboring next generation access nodes (NG-ANs) may terminate at the ANC. The ANC may include one or more TRPs 508 (which may also be referred to as BSs, NR BSs, Node Bs, 5G NBs, APs, gNB, or some other term). As described above, a TRP may be used interchangeably with “cell.”

The TRPs 508 may be a distributed unit (DU). The TRPs may be connected to one ANC (ANC 502) or more than one ANC (not illustrated). For example, for RAN sharing, radio as a service (RaaS), and service specific AND deployments, the TRP may be connected to more than one ANC. A TRP may include one or more antenna ports. The TRPs may be configured to individually (e.g., dynamic selection) or jointly (e.g., joint transmission) serve traffic to a UE.

The local architecture of RAN 500 may be used to illustrate fronthaul definition. The architecture may be defined that support fronthauling solutions across different deployment types. For example, the architecture may be based at least in part on transmit network capabilities (e.g., bandwidth, latency, and/or jitter).

The architecture may share features and/or components with LTE. According to aspects, the next generation AN (NG-AN) 510 may support dual connectivity with NR. The NG-AN may share a common fronthaul for LTE and NR.

The architecture may enable cooperation between and among TRPs 508. For example, cooperation may be preset within a TRP and/or across TRPs via the ANC 502. According to aspects, no inter-TRP interface may be needed/present.

According to aspects, a dynamic configuration of split logical functions may be present within the architecture of RAN 500. The packet data convergence protocol (PDCP), radio link control (RLC), media access control (MAC) protocol may be adaptably placed at the ANC or TRP.

According to various aspects, a BS may include a central unit (CU) (e.g., ANC 502) and/or one or more distributed units (e.g., one or more TRPs 508).

As indicated above, FIG. 5 is provided merely as an example. Other examples are possible and may differ from what was described with regard to FIG. 5.

FIG. 6 illustrates an example physical architecture of a distributed RAN 600, according to aspects of the present disclosure. A centralized core network unit (C-CU) 602 may host core network functions. The C-CU may be centrally deployed. C-CU functionality may be offloaded (e.g., to advanced wireless services (AWS)), in an effort to handle peak capacity.

A centralized RAN unit (C-RU) 604 may host one or more ANC functions. Optionally, the C-RU may host core network functions locally. The C-RU may have distributed deployment. The C-RU may be closer to the network edge.

A distributed unit (DU) 606 may host one or more TRPs. The DU may be located at edges of the network with radio frequency (RF) functionality.

As indicated above, FIG. 6 is provided merely as an example. Other examples are possible and may differ from what was described with regard to FIG. 6.

A UE and a BS may communicate using a set of channels, such as an uplink channel, a downlink channel, and/or the like. For example, the UE may provide uplink control information (UCI) bits to convey control information to the BS using a physical uplink control channel (PUCCH). The uplink channel may be associated with a format, which may define a quantity of symbols in a slot, a quantity of UCI bits that are provided as payload, and/or the like. For example, for PUCCH, format 0 may be associated with 1-2 symbols in a slot and less than or equal to 2 UCI bits, format 1 may be associated with 4-14 symbols in a slot and less than or equal to two UCI bits, format 2 may be associated with 1-2 symbols in a slot and greater than 2 UCI bits, and formats 3 and 4 may each be associated with 4-14 symbols in a slot and greater than 2 UCI bits.

The uplink channel may be modulated using a pre-configured modulation order. For example, for formats 2, 3, 4, and/or the like, the UE may modulate the PUCCH using quadrature phase shift keying (QPSK) modulation. The PUCCH may support other modulation orders, such as binary phase shift keying (BPSK) (e.g., π/2 BPSK), 8-phase shift keying (8PSK), quadrature amplitude modulation (QAM) (e.g., 16-QAM or a higher-order QAM)), and/or the like, such as for formats 2, 3, 4, and/or the like. However, using a relatively higher modulation order (e.g., 16-QAM) as a statically configured modulation order may result in poor coverage, such as when a UE is at a cell edge. Similarly, using a relatively lower modulation order (e.g., π/2 BPSK) as a statically configured modulation order may result in poor spectrum efficiency, such as when a UE is operating within a threshold proximity of a BS.

Some aspects, described herein, may enable dynamic modulation order control for an uplink channel. For example, a BS may provide, to a UE and while the UE is using a first modulation order for an uplink channel, a signaling message that identifies a second modulation order for the uplink channel. In this case, the UE may receive the signaling message, and may provide, to the BS, the uplink channel using the second modulation order. In this way, the BS and the UE may enable improved coverage and/or spectrum efficiency relative to a statically configured modulation order.

FIGS. 7A and 7B are diagrams illustrating an example 700 of modulation order control for a physical uplink control channel, in accordance with various aspects of the present disclosure. As shown in FIG. 7A, example 700 may include a BS 110 and a UE 120.

As further shown in FIG. 7A, and by reference number 705, UE 120 may provide a PUCCH to BS 110 using a first modulation order. For example, UE 120 may provide the PUCCH to BS 110 using QPSK modulation. As shown by reference number 710, UE 120 may provide a power headroom report to BS 110. For example, UE 120 may determine a transmit power of UE 120 to provide the PUCCH to BS 110, and may identify a power headroom for the transmit power. In this case, BS 110 may receive the power headroom report, and may identify a link budget for UE 120 based at least in part on the power headroom report. For example, BS 110 may identify the link budget based at least in part on a transmit power of UE 120 identified in the power headroom report, information identifying one or more other gains or losses, and/or the like.

As further shown in FIG. 7A, and by reference number 715, BS 110 may determine a second modulation order for UE 120. For example, based at least in part on the link budget, BS 110 may select the second modulation order, which may be different from the first modulation order. In some aspects, the second modulation order may be a lower modulation order than the first modulation order, such as π/2 BPSK relative to QPSK. In some aspects, the second modulation order may be a higher modulation order than the first modulation order, such as 8PSK, 16-QAM, another higher-order QAM, and/or the like.

In some aspects, BS 110 may determine that UE 120 is associated with less than a threshold link budget, and may select the second modulation order based at least in part on determining that UE 120 is associated with less than the threshold link budget. For example, when UE 120 is operating at a cell edge, UE 120 may use a relatively high transmit power to transmit the PUCCH. In this case, BS 110 may determine that UE 120 is associated with less than the threshold link budget, and may select for UE 120 to use BSPK to improve coverage for UE 120 relative to using QPSK and to avoid exceeding the threshold link budget.

Additionally, or alternatively, when UE 120 is operating at a cell center, such as in a cell center, UE 120 may use a relatively low transmit power to transmit the PUCCH. In this case, BS 110 may determine that UE 120 is associated with greater than the threshold link budget, and may select for UE 120 to use 8PSK, 16-QAM, and/or the like to improve spectrum efficiency, data rate, and/or the like relative to using QPSK and without exceeding the threshold link budget.

Additionally, or alternatively, when UE 120 is associated with a link budget in a threshold range, BS 110 may determine to maintain the first modulation order for UE 120. Although some aspects, described herein, are described in terms of UE 120 switching from QPSK to another modulation order, in some aspects, BS 110 may determine to cause UE 120 to transfer between other modulation orders, such as from π/2 BPSK to QPSK, π/2 BPSK to 16-QAM, 16-QAM to QPSK, and/or the like.

As shown in FIG. 7B, and by reference number 720, BS 110 may provide a signaling message to UE 120 that identifies the second modulation order for the PUCCH. For example, BS 110 may provide a radio resource control (RRC) message identifying 16-QAM as the second modulation order. Additionally, or alternatively, BS 110 may provide a signaling message identifying π/2 BPSK and/or the like. Additionally, or alternatively, BS 110 may provide dynamic signaling identifying the second modulation order, such as a message included in a physical downlink control channel (PDCCH).

As further shown in FIG. 7B, and by reference number 725, UE 120 may receive the signaling message (e.g., the RRC message or the dynamic signaling), and may determine to use the second modulation order for the PUCCH. In some aspects, the signaling message may identify one or more parameters, and UE 120 may determine the second modulation order to use based at least in part on the one or more parameters. For example, UE 120 may determine a PUCCH payload, a quantity of resource blocks assigned for the PUCCH, and/or the like. In this case, UE 120 may determine a PUCCH coding rate, and may determine the second modulation order based at least in part on the PUCCH coding rate. For example, less than a threshold coding rate range may correspond to using π/2 BPSK, within the threshold coding rate range may correspond to QPSK, greater than the threshold coding rate range may correspond to 16-QAM, and/or the like. In this way, BS 110 may signal and UE 120 may determine the second modulation order without using a dedicated indicator. As shown by reference number 730, UE 120 may provide, and BS 110 may receive, the PUCCH using the second modulation order. In this way, BS 110 and UE 120 may dynamically configure a modulation order for a physical uplink control channel, thereby improving coverage and/or spectrum efficiency relative to using a statically configured modulation order for a physical uplink control channel.

As indicated above, FIGS. 7A and 7B are provided as an example. Other examples are possible and may differ from what was described with respect to FIGS. 7A and 7B.

FIG. 8 is a diagram illustrating an example process 800 performed, for example, by a UE, in accordance with various aspects of the present disclosure. Example process 800 is an example where a UE (e.g., UE 120) performs modulation order control for a physical uplink control channel.

As shown in FIG. 8, in some aspects, process 800 may include receiving, while a UE is using a first modulation order for a physical uplink control channel, a signaling message that identifies a second modulation order, for the physical uplink control channel, wherein the second modulation order is different from the first modulation order (block 810). For example, the UE (e.g., using antenna 252, DEMOD 254, MIMO detector 256, receive processor 258, controller/processor 280, and/or the like) may receive the signaling message that identifies the second modulation order for the physical uplink control channel, as described above. In some aspects, the second modulation order may be different from the first modulation order. In some aspects, the signaling message is a radio resource control message or a dynamic signaling message. In some aspects, the UE may provide a power headroom report that includes information for identifying the link budget. In some aspects, the first modulation order is a quadrature phase shift keying format.

In some aspects, the physical uplink control channel supports greater than 2 bits of payload. In some aspects, the second modulation order is a π/2 binary phase shift keying format, an 8-phase shift keying format, a 16 quadrature amplitude modulation format, and/or the like.

In some aspects, the UE is associated with less than a threshold power headroom, and the UE is configured to switch from the first modulation order to the second modulation order to reduce a modulation order of the UE. In some aspects, the UE is associated with greater than or equal to a threshold power headroom, and the UE is configured to switch from the first modulation order to the second modulation order to increase a modulation order of the UE. In some aspects, the UE is associated with a particular power headroom, and the UE is configured to maintain the second modulation order to maintain a modulation order of the UE. In some aspects, the second modulation order is selected based at least in part on a link budget of the UE.

In some aspects, the signaling message includes information identifying one or more parameters associated with the second modulation order, and the UE identifies the second modulation order based at least in part on the one or more parameters.

As shown in FIG. 8, in some aspects, process 800 may include providing the physical uplink control channel using the second modulation order (block 820). For example, the UE (e.g., using controller/processor 280, transmit processor 264, TX MIMO processor 266, MOD 254, antenna 252, and/or the like) may provide the physical uplink control channel to a BS (e.g., BS 110) using the second modulation order based at least in part on receiving the signaling message from the BS identifying the second modulation order, as described above.

Process 800 may include additional aspects, such as any single aspect or any combination of aspects described above and/or in connection with one or more other processes described elsewhere herein.

Although FIG. 8 shows example blocks of process 800, in some aspects, process 800 may include additional blocks, fewer blocks, different blocks, or differently arranged blocks than those depicted in FIG. 8. Additionally, or alternatively, two or more of the blocks of process 800 may be performed in parallel.

FIG. 9 is a diagram illustrating an example process 900 performed, for example, by a BS, in accordance with various aspects of the present disclosure. Example process 900 is an example where a BS (e.g., BS 110) performs modulation order control for a physical uplink control channel.

As shown in FIG. 9, in some aspects, process 900 may include providing, while a UE is using a first modulation order for a physical uplink control channel, a signaling message that identifies a second modulation order, for the physical uplink control channel, wherein the second modulation order is different from the first modulation order (block 910). For example, the BS (e.g., using controller/processor 240, transmit processor 220, TX MIMO processor 230, MOD 232, antenna 234, and/or the like) may provide, to the UE (e.g., UE 120), the signaling message that identifies the second modulation order for the physical uplink control channel, as described above. In some aspects, the second modulation order may be different from the first modulation order.

In some aspects, the signaling message is a radio resource control message or a dynamic signaling message. In some aspects, the BS may receive a power headroom report that includes information for identifying the link budget. In some aspects, the first modulation order is a quadrature phase shift keying format.

In some aspects, the physical uplink control channel supports greater than 2 bits of payload. In some aspects, the second modulation order is a π/2 binary phase shift keying format, an 8-phase shift keying format, a 16 quadrature amplitude modulation format, and/or the like. In some aspects, the BS may identify the link budget of the UE, and may select the second modulation order, for the physical uplink control channel of the UE, based at least in part on the link budget of the UE.

In some aspects, the BS may determine, based at least in part on the link budget of the UE, that the UE is operating with less than a threshold power headroom; determine to cause a switch from the first modulation order to the second modulation order based at least in part on determining that the UE is operating with less than the threshold power headroom, wherein the second modulation order is less than the first modulation order; and provide the signaling message to cause the switch from the first modulation order to the second modulation order. In some aspects, the BS may determine, based at least in part on the link budget of the UE, that the UE is operating with greater than or equal to a threshold power headroom; determine to cause a switch from the first modulation order to the second modulation order based at least in part on determining that the UE is operating with greater than or equal to the threshold power headroom, wherein the second modulation order is greater than the first modulation order; and provide the signaling message to cause the switch from the first modulation order to the second modulation order.

In some aspects, the BS may determine, based at least in part on the link budget of the UE and after receiving the physical uplink control channel using the second modulation order, that the UE is operating with a particular power headroom; and may cause the UE to maintain the second modulation order. In some aspects, the second modulation order is selected based at least in part on a link budget of the UE.

In some aspects, the signaling message includes information identifying one or more parameters associated with the second modulation order, and the UE identifies the second modulation order based at least in part on the one or more parameters.

As shown in FIG. 9, in some aspects, process 900 may include receiving the physical uplink control channel using the second modulation order (block 920). For example, the BS (e.g., using antenna 234, DEMOD 232, MIMO detector 236, receive processor 238, controller/processor 240, and/or the like) may receive the physical uplink control channel, from the UE, using the second modulation order based at least in part on providing the signaling message identifying the second modulation order for the physical uplink control channel, as described above.

Process 900 may include additional aspects, such as any single aspect or any combination of aspects described above and/or in connection with one or more other processes described elsewhere herein.

Although FIG. 9 shows example blocks of process 900, in some aspects, process 900 may include additional blocks, fewer blocks, different blocks, or differently arranged blocks than those depicted in FIG. 9. Additionally, or alternatively, two or more of the blocks of process 900 may be performed in parallel.

The foregoing disclosure provides illustration and description, but is not intended to be exhaustive or to limit the aspects to the precise form disclosed. Modifications and variations are possible in light of the above disclosure or may be acquired from practice of the aspects.

As used herein, the term component is intended to be broadly construed as hardware, firmware, or a combination of hardware and software. As used herein, a processor is implemented in hardware, firmware, or a combination of hardware and software.

Some aspects are described herein in connection with thresholds. As used herein, satisfying a threshold may refer to a value being greater than the threshold, greater than or equal to the threshold, less than the threshold, less than or equal to the threshold, equal to the threshold, not equal to the threshold, and/or the like.

It will be apparent that systems and/or methods, described herein, may be implemented in different forms of hardware, firmware, or a combination of hardware and software. The actual specialized control hardware or software code used to implement these systems and/or methods is not limiting of the aspects. Thus, the operation and behavior of the systems and/or methods were described herein without reference to specific software code—it being understood that software and hardware can be designed to implement the systems and/or methods based, at least in part, on the description herein.

Even though particular combinations of features are recited in the claims and/or disclosed in the specification, these combinations are not intended to limit the disclosure of possible aspects. In fact, many of these features may be combined in ways not specifically recited in the claims and/or disclosed in the specification. Although each dependent claim listed below may directly depend on only one claim, the disclosure of possible aspects includes each dependent claim in combination with every other claim in the claim set. A phrase referring to “at least one of” a list of items refers to any combination of those items, including single members. As an example, “at least one of: a, b, or c” is intended to cover a, b, c, a-b, a-c, b-c, and a-b-c, as well as any combination with multiples of the same element (e.g., a-a, a-a-a, a-a-b, a-a-c, a-b-b, a-c-c, b-b, b-b-b, b-b-c, c-c, and c-c-c or any other ordering of a, b, and c).

No element, act, or instruction used herein should be construed as critical or essential unless explicitly described as such. Also, as used herein, the articles “a” and “an” are intended to include one or more items, and may be used interchangeably with “one or more.” Furthermore, as used herein, the terms “set” and “group” are intended to include one or more items (e.g., related items, unrelated items, a combination of related and unrelated items, and/or the like), and may be used interchangeably with “one or more.” Where only one item is intended, the term “one” or similar language is used. Also, as used herein, the terms “has,” “have,” “having,” and/or the like are intended to be open-ended terms. Further, the phrase “based on” is intended to mean “based, at least in part, on” unless explicitly stated otherwise. 

What is claimed is:
 1. A method of wireless communication performed by a user equipment (UE) of a cellular network, comprising: receiving, while the UE is using a first modulation order for a physical uplink control channel (PUCCH), a signaling message from a base station of the cellular network that identifies a second modulation order, for the physical uplink control channel, wherein the second modulation order is different from the first modulation order; determining one of a PUCCH format 3 and a PUCCH format 4, when the second modulation order comprises a π/2 BPSK modulation, upon receiving the signaling message and based in part on the received signaling message; and transmitting an uplink control channel using the second modulation order and the determined PUCCH format.
 2. The method of claim 1, wherein the signaling message is a radio resource control message or a dynamic signaling message.
 3. The method of claim 1, further comprising: providing a power headroom report, wherein the power headroom report includes information for identifying the link budget.
 4. The method of claim 1, wherein the first modulation order is a quadrature phase shift keying format.
 5. The method of claim 1, wherein the physical uplink control channel supports greater than 2 bits of payload.
 6. The method of claim 1, wherein the UE is associated with less than a threshold power headroom, and wherein the UE is configured to switch from the first modulation order to the second modulation order to reduce a modulation order of the UE.
 7. The method of claim 1, wherein the UE is associated with greater than or equal to a threshold power headroom, and wherein the UE is configured to switch from the first modulation order to the second modulation order to increase a modulation order of the UE.
 8. The method of claim 1, wherein the UE is associated with a particular power headroom, and wherein the UE is configured to maintain the second modulation order to maintain a modulation order of the UE.
 9. The method of claim 1, wherein the second modulation order is selected based at least in part on a link budget of the UE.
 10. A method of wireless communication performed by a base station (BS) of a cellular network, comprising: determining one of a physical uplink control channel (PUCCH) format 3 and a PUCCH format 4, and a second modulation order comprising a π/2 BPSK modulation for a physical uplink control channel; providing, while a user equipment (UE) is using a first modulation order for the physical uplink control channel, a signaling message of the cellular network to the UE that indicates the second modulation order, upon determining the PUCCH format and the second modulation order, for the physical uplink control channel, wherein the second modulation order is different from the first modulation order; and receiving the physical uplink control channel using the second modulation order and the determined PUCCH format.
 11. The method of claim 10, wherein the signaling message is a radio resource control message or a dynamic signaling message.
 12. The method of claim 10, further comprising: receiving a power headroom report, wherein the power headroom report includes information for identifying the link budget.
 13. The method of claim 10, wherein the first modulation order is a quadrature phase shift keying format.
 14. The method of claim 10, wherein the physical uplink control channel supports greater than 2 bits of payload.
 15. The method of claim 10, further comprising: identifying the link budget of the UE; and selecting the second modulation order, for the physical uplink control channel of the UE, based at least in part on the link budget of the UE.
 16. The method of claim 10, further comprising: determining, based at least in part on the link budget of the UE, that the UE is operating with less than a threshold power headroom; determining to cause a switch from the first modulation order to the second modulation order based at least in part on determining that the UE is operating with less than the threshold power headroom, wherein the second modulation order is less than the first modulation order; and wherein provide the signaling message comprises: providing the signaling message to cause the switch from the first modulation order to the second modulation order.
 17. The method of claim 10, further comprising: determining, based at least in part on the link budget of the UE, that the UE is operating with greater than or equal to a threshold power headroom; determining to cause a switch from the first modulation order to the second modulation order based at least in part on determining that the UE is operating with greater than or equal to the threshold power headroom, wherein the second modulation order is greater than the first modulation order; and wherein providing the signaling message comprises: providing the signaling message to cause the switch from the first modulation order to the second modulation order.
 18. The method of claim 10, further comprising: determining, based at least in part on the link budget of the UE and after receiving the physical uplink control channel using the second modulation order, that the UE is operating with a particular power headroom; and causing the UE to maintain the second modulation order.
 19. The method of claim 10, wherein the second modulation order is selected based at least in part on a link budget of the UE.
 20. A user equipment (UE) of a cellular network for wireless communication, comprising: a memory; and one or more processors operatively coupled to the memory, the memory and the one or more processors configured to: receive, while the UE is using a first modulation order for a physical uplink control channel (PUCCH), a signaling message from a base station of the cellular network that identifies a second modulation order, for the physical uplink control channel, wherein the second modulation order is different from the first modulation order; determine one of a PUCCH format 3 and a PUCCH format 4, when the second modulation order comprises π/2 BPSK modulation upon receiving the signaling message and based in part on the received signaling message; and transmit an uplink control channel using the second modulation order and the determined PUCCH format.
 21. The UE of claim 20, wherein the signaling message is a radio resource control message or a dynamic signaling message.
 22. The UE of claim 20, wherein the one or more processors are further configured to: provide a power headroom report, wherein the power headroom report includes information for identifying the link budget.
 23. The UE of claim 20, wherein the first modulation order is a quadrature phase shift keying format.
 24. The UE of claim 20, wherein the physical uplink control channel supports greater than 2 bits of payload.
 25. The UE of claim 20, wherein the UE is associated with less than a threshold power headroom, and wherein the UE is configured to switch from the first modulation order to the second modulation order to reduce a modulation order of the UE.
 26. The UE of claim 20, wherein the UE is associated with greater than or equal to a threshold power headroom, and wherein the UE is configured to switch from the first modulation order to the second modulation order to increase a modulation order of the UE.
 27. The UE of claim 20, wherein the UE is associated with a particular power headroom, and wherein the UE is configured to maintain the second modulation order to maintain a modulation order of the UE.
 28. The UE of claim 20, wherein the second modulation order is selected based at least in part on a link budget of the UE.
 29. A base station (BS) of a cellular network for wireless communication, comprising: a memory; and one or more processors operatively coupled to the memory, the memory and the one or more processors configured to: determine one of a physical uplink control channel (PUCCH) format 3 and a PUCCH format 4, and a second modulation order comprising a π/2 BPSK modulation for a physical uplink control channel; provide, while a user equipment (UE) is using a first modulation order for the physical uplink control channel, a signaling message of the cellular network to the UE that indicates the second modulation order, upon determining the PUCCH format and the second modulation order, for the physical uplink control channel, wherein the second modulation order is different from the first modulation order; and receiving the physical uplink control channel using the second modulation order and the determined PUCCH format.
 30. The BS of claim 29, wherein the signaling message is a radio resource control message or a dynamic signaling message.
 31. The BS of claim 29, wherein the one or more processors are further configured to: receive a power headroom report, wherein the power headroom report includes information for identifying the link budget.
 32. The BS of claim 29, wherein the first modulation order is a quadrature phase shift keying format.
 33. The BS of claim 29, wherein the physical uplink control channel supports greater than 2 bits of payload.
 34. The BS of claim 29, wherein the one or more processors are further configured to: identify the link budget of the UE; and select the second modulation order, for the physical uplink control channel of the UE, based at least in part on the link budget of the UE.
 35. The BS of claim 29, wherein the one or more processors are further configured to: determine, based at least in part on the link budget of the UE, that the UE is operating with less than a threshold power headroom; determine to cause a switch from the first modulation order to the second modulation order based at least in part on determining that the UE is operating with less than the threshold power headroom, wherein the second modulation order is less than the first modulation order; and wherein the one or more processors, when configured to provide the signaling message, are configured to: provide the signaling message to cause the switch from the first modulation order to the second modulation order.
 36. The BS of claim 29, wherein the one or more processors are further configured to: determine, based at least in part on the link budget of the UE, that the UE is operating with greater than or equal to a threshold power headroom; determine to cause a switch from the first modulation order to the second modulation order based at least in part on determining that the UE is operating with greater than or equal to the threshold power headroom, wherein the second modulation order is greater than the first modulation order; and wherein the one or more processors, when configured to provide the signaling message, are configured to: provide the signaling message to cause the switch from the first modulation order to the second modulation order.
 37. The BS of claim 29, wherein the one or more processors are further configured to: determine, based at least in part on the link budget of the UE and after receiving the physical uplink control channel using the second modulation order, that the UE is operating with a particular power headroom; and cause the UE to maintain the second modulation order.
 38. The BS of claim 29, wherein the second modulation order is selected based at least in part on a link budget of the UE.
 39. A non-transitory computer-readable medium storing one or more instructions for wireless communication, the one or more instructions comprising: one or more instructions that, when executed by one or more processors of a user equipment (UE) of a cellular network, cause the one or more processors to: receive, while the UE is using a first modulation order for a physical uplink control channel (PUCCH), a signaling message from a base station of the cellular network that identifies a second modulation order, for the physical uplink control channel, wherein the second modulation order is different from the first modulation order; determine one of a PUCCH format 3 and a PUCCH format 4, when the second modulation order comprises π/2 BPSK modulation upon receiving the signaling message and based in part on the received signaling message; and transmit an uplink control channel using the second modulation order and the determined PUCCH format.
 40. The non-transitory computer-readable medium of claim 39, wherein the signaling message is a radio resource control message or a dynamic signaling message.
 41. The non-transitory computer-readable medium of claim 39, wherein the one or more instructions, when executed by the one or more processors, further cause the one or more processors to: provide a power headroom report, wherein the power headroom report includes information for identifying the link budget.
 42. The non-transitory computer-readable medium of claim 39, wherein the first modulation order is a quadrature phase shift keying format.
 43. The non-transitory computer-readable medium of claim 39, wherein the physical uplink control channel supports greater than 2 bits of payload.
 44. The non-transitory computer-readable medium of claim 39, wherein the UE is associated with less than a threshold power headroom, and wherein the UE is configured to switch from the first modulation order to the second modulation order to reduce a modulation order of the UE.
 45. The non-transitory computer-readable medium of claim 39, wherein the UE is associated with greater than or equal to a threshold power headroom, and wherein the UE is configured to switch from the first modulation order to the second modulation order to increase a modulation order of the UE.
 46. The non-transitory computer-readable medium of claim 39, wherein the UE is associated with a particular power headroom, and wherein the UE is configured to maintain the second modulation order to maintain a modulation order of the UE.
 47. The non-transitory computer-readable medium of claim 39, wherein the second modulation order is selected based at least in part on a link budget of the UE.
 48. A non-transitory computer-readable medium storing one or more instructions for wireless communication, the one or more instructions comprising: one or more instructions that, when executed by one or more processors of a base station (BS) of a cellular network, cause the one or more processors to: determine one of a physical uplink control channel (PUCCH) format 3 and a PUCCH format 4, and a second modulation order comprising a π/2 BPSK modulation for a physical uplink control channel; provide, while a user equipment (UE) is using a first modulation order for the physical uplink control channel, a signaling message of the cellular network to the UE that a indicates the second modulation order, upon determining the PUCCH format and the second modulation order, for the physical uplink control channel, wherein the second modulation order is different from the first modulation order; and receive the physical uplink control channel using the second modulation order and the determined PUCCH format.
 49. The non-transitory computer-readable medium of claim 48, wherein the signaling message is a radio resource control message or a dynamic signaling message.
 50. The non-transitory computer-readable medium of claim 48, wherein the one or more instructions, when executed by the one or more processors, further cause the one or more processors to: receive a power headroom report, wherein the power headroom report includes information for identifying the link budget.
 51. The non-transitory computer-readable medium of claim 48, wherein the first modulation order is a quadrature phase shift keying format.
 52. The non-transitory computer-readable medium of claim 48, wherein the physical uplink control channel supports greater than 2 bits of payload.
 53. The non-transitory computer-readable medium of claim 48, wherein the one or more instructions, when executed by the one or more processors, further cause the one or more processors to: identify the link budget of the UE; and select the second modulation order, for the physical uplink control channel of the UE, based at least in part on the link budget of the UE.
 54. The non-transitory computer-readable medium of claim 48, wherein the one or more instructions, when executed by the one or more processors, further cause the one or more processors to: determine, based at least in part on the link budget of the UE, that the UE is operating with less than a threshold power headroom; determine to cause a switch from the first modulation order to the second modulation order based at least in part on determining that the UE is operating with less than the threshold power headroom, wherein the second modulation order is less than the first modulation order; and wherein the one or more instructions, that cause the one or more processors to provide the signaling message, cause the one or more processors to: provide the signaling message to cause the switch from the first modulation order to the second modulation order.
 55. The non-transitory computer-readable medium of claim 48, wherein the one or more instructions, when executed by the one or more processors, further cause the one or more processors to: determine, based at least in part on the link budget of the UE, that the UE is operating with greater than or equal to a threshold power headroom; determine to cause a switch from the first modulation order to the second modulation order based at least in part on determining that the UE is operating with greater than or equal to the threshold power headroom, wherein the second modulation order is greater than the first modulation order; and wherein the one or more instructions, that cause the one or more processors to provide the signaling message, cause the one or more processors to: provide the signaling message to cause the switch from the first modulation order to the second modulation order.
 56. The non-transitory computer-readable medium of claim 48, wherein the one or more instructions, when executed by the one or more processors, further cause the one or more processors to: determine, based at least in part on the link budget of the UE and after receiving the physical uplink control channel using the second modulation order, that the UE is operating with a particular power headroom; and cause the UE to maintain the second modulation order.
 57. The non-transitory computer-readable medium of claim 48, wherein the second modulation order is selected based at least in part on a link budget of the UE. 